Device for linking two webs of material

ABSTRACT

Two webs of material, each rolled on a separate roll of material, are linked or spaced together during a web-roll change, without stoppage of the web travel. A linking or splicing device is used for linking, particularly by gluing the fresh web of material to the exhausting web. A cutting device is used to produce two web ends. The cutting device is located downstream of the linking or splicing device, as seen in a direction of travel of the expiring or exhausting web of material.

FIELD OF THE INVENTION

The present invention is directed to a device for connecting two webs ofmaterial during a flying roll change. A connecting device is used toconnect the two webs and a cutting device is used to cut the exhaustingweb from its roll once the webs have been connected.

BACKGROUND OF THE INVENTION

A device for accomplishing a flying roll change is known from DE 42 18825 A1. A fresh paper web can be glued to the paper web which isrunning-out in a printing press operating at production speed. After thefresh paper web has been glued on, the paper web which is running-out iscut by use of a cutting device and two web ends are formed in theprocess. The one web end, together with the fresh paper web, is conveyedthrough the printing press, and the second web end, together with theused up paper roll, can be removed from the roll changer. In the courseof the roll change, both paper rolls rotate in the same direction, andthe running-out paper web is moved past the fresh paper roll in such away that, in the course of gluing it to the running-out paper web, thestart of the fresh paper web is brought into contact with therunning-out paper web in as tangentially a way as possible.

Another device for accomplishing a flying roll change is known from U.S.Pat No. 4,936,942, wherein a cutting device and a gluing roller areprovided in a frame. For a roll change, the frame can approach therunning-out paper web from one side, so that when the connecting deviceis triggered, a gluing roller, together with the running-out paper web,is pressed against a gluing spot of the fresh paper web. Thereafter, therunning-out paper web is cut by the cutting knife.

Yet another device for accomplishing a flying roll change is known fromEP 0 720 581 B1. The tension of the paper web can be kept substantiallyconstant during the gluing or cutting process by a suitable kinematicmovement process.

In connection with the generally known devices for connecting two paperwebs in the course of a flying roll change, it is disadvantageous that,because of the arrangement of the connecting device, for example agluing roller or gluing brush, downstream of the cutting device, in thefeed direction of the running-out web of material, a so-called “slip” isnecessarily formed. In this case, the length of this slip, i.e. thedistance between the connecting point of the fresh and the old web ofmaterial and the cut-through web end of the old web of material, isessentially determined by the distance between the connecting device andthe cutting device. Interferences are often caused by the slip in thecourse of conveying the web of material through a processing machine,for example a web-fed rotary printing press. To prevent theseinterferences, a device is proposed in WO 99/40004 A1, wherein, by useof an appropriate web guidance after the cutting of the old web ofmaterial, the slip is pushed outwardly by the centrifugal forces actingon the slip and is subsequently cut off by a cutter bar. It is possiblewith this to shorten the length of the slip to almost zero. However, aconsiderable additional structural outlay is required for an appropriateweb guidance and for the downstream connected cutter bar.

SUMMARY OF THE INVENTION

The object of the present invention, is directed to providing a devicefor connecting two webs of material.

In accordance with the present invention, this object is attained byconnecting the two webs of material, each wound on a separate roll,during a flying roll change. A connecting device is provided forconnecting the fresh web of material with the exhausting web ofmaterial. A cutting device is used to cut the exhausting web once theconnection has been made. The cutting device and the exhausting web,which is to be cut, are brought into engagement by changing the courseof travel of the web to be cut.

The advantages to be obtained by the present invention lie, inparticular, in that, because of the arrangement of the cutting devicedownstream of the connecting device, viewed in the feeding direction ofthe running-out web of material, the slip can be basically cut off asshort as desired when the running-out web of material is cut. Whenconnecting the fresh web of material to the running-out web of material,the result always is a Y-shaped structure, one of whose branches, namelythe old web of material starting at the old roll of material up to thegluing point, can essentially be completely cut off by the cuttingdevice which is arranged downstream of the connecting device. Byarranging the cutting device downstream of the connecting device, nominimum slip length necessarily results, but the length of the slip canbasically be shortened as desired. However, in the course of this, itshould be noted that, if the slip length is selected to be too short,there is the potential danger that the fresh web of material isinadvertently damaged by the cutting device.

If the cutting device is arranged downstream of the connecting device,there is the potential danger that the fresh web of material is alsoinadvertently damaged in the course of cutting through the old web ofmaterial. To reliably prevent this danger, it is particularlyadvantageous if the cutting device is brought into engagement with theweb of material to be cut by moving a web guide device, by which thecourse of the web of material to be cut can be changed. As a result, itis possible to accomplish that the fresh web of material and the web ofmaterial to be cut off are guided along different paths in the areadownstream of the gluing point, so that only the old web of material iscut. By moving the web guide device, it is, in particular, possible forthe fresh web of material and the web of material to be cut to form adefined angle with respect to each other. In this case, the cuttingdevice for cutting the old web of material must be arranged in such away that, after the gluing point has passed the cutting device, becauseof its course the old web of material can be cut by contact with thecutting edge of the cutting device. An advantage of this configurationresides, in particular, in that the cutting device for cutting the oldweb of material need not be moved, but can be arranged fixed in oneplace.

The change of the course of the old web of material, which is requiredfor cutting the old web of material, can be achieved in a particularlysimple manner. The connecting device, for example a gluing roller orgluing brush, after it has pressed the running-out web of materialagainst the fresh web of material, is displaced in such a way that theold web of material comes into engagement with the cutting device.

Alternatively to the displacement of a web guide device, by which thecourse of the web of material to be cut can be altered, it is alsopossible that the cutting device will come into engagement with the webof material to be cut by use of a suitable displacement of a web guidedevice, by which the course of the fresh web of material can be changed,and which will accomplish the simultaneous change of position of thecutting device. In other words, this means that by changing the webguide device, the fresh web of material is rerouted, at least briefly,in such a way that after the position of the cutting device has beenchanged, the fresh web of material does not come into engagement withthe cutting device, and only the old web of material is cut by thechange of position of the cutting device.

In order to reliably prevent an unintentional cutting of the fresh webof material by the cutting device, a spacing element can be provided onthe cutting device. By use of the spacing element, a defined minimumdistance between the cutting device and the fresh web of material isassured.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are represented in thedrawings and will be described in greater detail in what follows.

Shown are in:

FIG. 1, a schematic side elevation view of a device for connecting twowebs of material in accordance with the present invention and in aninitial position,

FIG. 2, the device of FIG. 1 after the running-out web of material hasapproached the fresh web of material,

FIG. 3, the device of FIG. 1 in the course of pressing the running-outweb of material against the fresh web of material, and in

FIG. 4, the device of FIG. 1 in the course of cutting the old web ofmaterial.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A device 01 for linking two webs of material in accordance with thepresent invention and with a web connecting device 02, that is embodiedin the manner of a gluing roller, in particular a web guide device, anda web cutting device 03, which web cutting device 03 is embodied in themanner of a severing cutter, are represented in FIG. 1. Both the webconnecting device 02 and the web cutting device 03 are fastened on aframe 04, with frame 04 being formed by two lateral elements that arearranged parallel with each other. Two pivot arms 07, which are eachseated for pivoting around an axis of rotation 06, are provided for usein displacing the web connecting device 02 in relation to the frame 04.The web connecting device 02 can be rotatingly pivoted around the axisof rotation 06 by triggering a drive mechanism, which is notspecifically represented. The web connecting device 02 is embodied inthe manner of a gluing roller and is rotatably seated at the lower endsof the pivot arms 07. The cutting device 03 is connected with the frame04 and is fixed in place on it. The frame 04 itself is pivotably seatedand can be pivoted around a frame axis of rotation 08, which is the sameas, and is aligned with an axis of rotation of a guide roller 09. Theframe 04 is pivotable about its axis of rotation 08 by use of a drivedevice, which is not specifically represented.

FIG. 1 represents the device for linking webs, 01 in its initialposition. In the initial position, the device 01 has been pivoted to theright in such a way that neither the cutting device 03 nor the webconnecting device 02 come into engagement with one of the webs ofmaterial. A running-out or exhausting web of material 11, in particulara paper web, is wound off a depleted roll of material 15, which depletedroll of material 15 is seated in a roll changer, not represented. Web ofmaterial 11 is conveyed into a downstream arranged device, for example arotary printing press, over the web guide rollers 12, 09. The conveyingdirection of the running-out or exhausting web of material 11 can bedetermined by the movement arrow 13.

If the old or depleted roll of material 15 is used up to a large extent,and if therefore a flying roll change is to be performed, a fresh orfull roll of material 14, on which a fresh web of material 16, inparticular a paper web, is wound, is clamped into the roll changer,which is not specifically represented, and is rotationally acceleratedin accordance with the movement arrow 17 until the circumferential speedof a web start 18 of the fresh web of material 16 matches the conveyingspeed of the running-out or exhausting web of material 11. Adhesivelabels 19 have been attached to the web start 18 of the fresh web ofmaterial 16, so that the fresh web of material 16 can be connected withthe running-out or exhausting web of material 11. The passage of theadhesive labels 19 can be detected by utilization of a sensor 21, whichis only represented schematically, and can be passed on to the controlof the roll changer. As soon as the fresh web of material 14 has reachedthe required circumferential speed, the frame 04 can be pivoted to theleft in accordance with the movement arrow 22 so that the running-out orexhausting web of material 11 initially approaches the fresh roll ofmaterial 14.

The device for linking webs, 01, is represented in FIG. 2 after thepivoting of the frame 04, for letting the running-out web of material 11approach the fresh roll of material 14, has been accomplished. In thecourse of the pivot movement of the frame 04, the web connecting devicepivot arms 07 are also pivoted without their moving relative to theframe 04. The result is that the web connecting device 02 now comes intocontact with one side of the running-out or exhausting web of material11 and, with an increasing pivot angle of the frame 04, the webconnecting device 02 pushes the running-out or exhausting web ofmaterial 11 farther and farther in the direction of the fresh roll ofmaterial 14. Since the pivot arms 07 have not yet been displaced, damageto the running-out or exhausting web of material 11 by the cuttingdevice 03, which is fixedly mounted on the frame, is prevented becauseof the relative arrangement between the web cutting device 03 and theweb connecting device 02.

Once the web connecting device 02 has sufficiently approached the freshroll of material 14 by effecting the pivoting of the frame 04, it ispossible to start the actual connection of the running-out web ofmaterial 11 with the fresh web of material 16. To this end, a signal ispassed on from the sensor 21 to the control device when the adhesivelabels 19 pass, so that after receipt of this signal, the control devicetriggers the drive mechanism for displacing the pivot arms 07. The pivotarms 07, which support the web connecting device 02, are pivoted to theleft, in accordance with the movement arrow 23, and, in the process,move the running-out or exhausting web of material 11 along until therunning-out or exhausting web of material 11 comes to rest against thefresh roll of material 14 at the exact moment of the passage of theadhesive labels 19. The web start 18 of the fresh web of material 16 isnow connected with one side of the old running-out or exhausting web ofmaterial 11.

The configuration of the device for linking webs, 01, at the exactmoment of the connection between the running-out or exhausting web ofmaterial 11 and the fresh web of material 16 is schematically depictedin FIG. 3. It can be seen, by referring to FIG. 4, that, because of theconnection of the fresh web of material 16 with one side of therunning-out or exhausting web of material 11, a Y-shaped structureresults, two of whose branches are formed by the running-out orexhausting web of material 11, and one of whose branches is formed bythe fresh web of material 16, and in whose juncture the adhesive labels19 are located. An unintentional cutting of the running-out web ofmaterial 11 at this time is not possible since, because of thearrangement of the cutting device 03 on the frame 04, the cutting device03 extends essentially parallel with the course of travel of therunning-out or exhausting web of material 11 in the area of the frame04. Furthermore, a circular spacing element 24 is provided on the webcutting device 03, because of which, a defined minimum distance betweenthe running-out or exhausting web of material 11 and the cutting edge ofthe cutting device 03 is maintained.

To finish the flying roll change, it is necessary to cut the old web ofmaterial 11, which up to this time has constituted the running-out orexhausting web of material 11. In order to cut the old web of material11, without any danger of damage to the fresh web of material 16, thepivot arms 07 are controlled in such a way that they are now pivotedback toward the right in accordance with the movement arrow 26, whicharrow 26 is shown in FIG. 3. The course of the old web of material 11 ischanged in the area downstream of the gluing point by this pivotmovement, so that, as a function of the setting angle of the pivot arms07, the fresh web of material 16 and the old web of material 11 togetherform a defined angle a, as seen in FIG. 4, in the area of the gluingpoint.

The device for linking webs, 01, is depicted in FIG. 4 at the exactmoment of the passage of the adhesive labels 19 past the cutting device03. At this time, the web connecting device pivot arms 07 have beenpivoted back far enough so that the web connecting device 02 just restsagainst the old web of material 11. The fresh web of material 16 extendsunder tension between the adhesive labels 19 and the fresh roll ofmaterial 14. As soon as the adhesive labels 19 pass the cutting device03, the old web of material 11 is cut by the cutting device 03 becauseof the course of travel of this old web. The slip or trail of the nowcut old web 11, which is being created in the course of this cutting isonly as long as the distance between the cutting edge of the cuttingdevice 03 and the splice point for the fresh web of material 16.

Thereafter, the fresh web of material 16 is conveyed into the downstreamlocated device 01 and the old roll of material 15, together with the cutoff web end, is removed from the roll changer. The frame 04 is thenpivoted back, in accordance with the movement arrow 27, into its initialposition, as represented in FIG. 1.

While a preferred embodiment of a device for linking two webs ofmaterial in accordance with the present invention has been set forthfully and completely hereinabove, it will be apparent to one of skill inthe art that various changes in, for example, the type of printing pressbeing used, the overall width of the web being cut and the like could bemade without departing from the true spirit and scope of the presentinvention which is to be limited only by the following claims.

What is claimed is:
 1. A device for connecting webs of material wound onrolls during a flying roll change comprising: a web connecting deviceuseable to move an exhausting web of material into contact with a freshweb of material to connect the exhausting web of material, moving in aweb direction of travel, with the fresh web of material; a web cuttingdevice engageable with the exhausting web of material for cutting theexhausting web of material subsequent to said connection; and means forchanging a course of travel of the exhausting web of material subsequentto said connection for engaging said web cutting device with theexhausting web of material to be cut.
 2. The device of claim 1 whereinsaid web cutting device is arranged after said web connecting device, inthe web a direction of travel of exhausting web of material.
 3. Thedevice of claim 2 wherein said web connecting device is a gluing roller.4. The device of claim 1 wherein said web connecting device isdisplaceable and further wherein said web cutting device is engageablewith the exhausting web of material to be cut by displacement of saidweb connecting device.
 5. The device of claim 4 wherein saiddisplacement of said web connecting device displaces the fresh web ofmaterial.
 6. The device of claim 1 wherein said web cutting device isparallel with a path of travel of the fresh web of material during theconnection of the fresh web of material to the exhausting web ofmaterial.
 7. The device of claim 1 further including a spacing elementfor said web cutting device, said spacing element being usable to definea measured minimum distance between a cutting edge of said cuttingdevice, and the fresh web of material.
 8. The device of claim 1 furtherincluding a displaceable frame supporting at least one of said webconnecting device and said web cutting device.
 9. The device of claim 8wherein said frame is displaced forward and away from the fresh roll ofmaterial.
 10. The device of claim 8 wherein said cutting device issecured on said frame and further wherein said web connecting device isdisplaced on said frame, the exhausting web of material to be cut beingengageable with said web cutting device by displacement of saiddisplaceable web connecting device.